title: Interleukin-13/Interleukin-4-induced oxidative stress contributes to death of prothrombinkringle-2 (pKr-2)-activated microglia.
abstract: The present study examined whether Interleukin-13 (IL-13) or IL-4, an anti-inflammatory cytokine, could induce cell death of activated microglia by prothrombin kringle-2 (pKr-2) which is a domain of prothrombin distinct from thrombin. Microglia cell death was detected at eight days after co-treatment of pKr-2 with IL-13/IL-4 in vitro. This cell death was assessed by live assay, dead assay, TUNEL and MTT assay. In parallel, reactive oxygen species (ROS) production was evident as assessed by superoxide assay, WST-1 and analyzing DCF in combination of pKr-2 and IL-13 or IL-4 treated microglia. The IL-13/IL-4-enhanced ROS production and cell death in pKr-2 activated microglia was partially inhibited by an NADPH oxidase inhibitor, apocynin and/or by several antioxidants. Moreover, Western blot analysis showed a significant increase in cyclooxygenase-2 (COX-2) expression in combination of pKr-2 and IL-13 or IL-4 treated microglia, which was partially inhibited by apocynin and an antioxidant, trolox. Additional studies demonstrated that microglia cell death was reversed by treatment with COX-2 inhibitor, NS398. Our data strongly suggest that oxidative stress and COX-2 activation through NADPH oxidase may contribute to IL-13/IL-4 induced cell death of pKr-2 activated microglia.
authors.affiliation: Department of Biochemistry and Medical Research Center, Chungbuk National University College of Medicine, Cheongju 361-763, South Korea.
authors.forename: So-Yoon
authors.initials: SY
authors.lastname: Won
authors.forename: Sang Ryong
authors.initials: SR
authors.lastname: Kim
authors.forename: Sungho
authors.initials: S
authors.lastname: Maeng
authors.forename: Byung K
authors.initials: BK
authors.lastname: Jin
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D051546:Cyclooxygenase 2 / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D020287:In Situ Nick-End Labeling; D018793:Interleukin-13 / Q000494:pharmacology*; D015847:Interleukin-4 / Q000494:pharmacology*; D018082:Kringles; D017628:Microglia / Q000187:drug effects* / Q000378:metabolism*; D019255:NADPH Oxidases / Q000378:metabolism; D009578:Nitrobenzenes / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects*; D011516:Prothrombin / Q000737:chemistry* / Q000494:pharmacology; D051381:Rats; D013449:Sulfonamides / Q000494:pharmacology; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: C110656:2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium; D000098:Acetophenones; D004791:Enzyme Inhibitors; D018793:Interleukin-13; D009578:Nitrobenzenes; D013449:Sulfonamides; D013778:Tetrazolium Salts; D013844:Thiazoles; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D015847:Interleukin-4; D011516:Prothrombin; C056165:acetovanillone; D051546:Cyclooxygenase 2; C489691:Ptgs2 protein, rat; D019255:NADPH Oxidases; C022616:thiazolyl blue
keywords: COX-2; Interleukin-13; Interleukin-4; Microglia; NADPH oxidase; Prothrombin kringle-2